using Data Block Wizard, create a master block. Its base table is EMP, the only column you'll choose is DEPTNO

create its layout - form style (which means that you'll see only one item on a canvas)

create another block (using Data Block Wizard again). It will be a detail block.

Its base table is EMP again. This time select ALL items.

Create master-detail relationship (manually, within the Wizard) by joining DEPTNO items from both blocks

layout should be "tabular"; display as many records as you wish (10, for example)

run the form. While in master block, perform query. It (master block) will contain 14 records (if the EMP table is the "original" one), and you'll scroll through 14 DEPTNO values (some of them will be duplicate, of course). Detail records will automatically change, as you scroll through master records

The above all are text items the master block has Deptno and Sal.
The detail block has Empno, Ename, Deptno, Sal.
The detail block should display multiple records.
The relation is the Deptno
Based on the Deptno,Sal the details should be queried as well as when key in the new data it stores multiple records like..

If we create like how Littlefoot explained, will it work? In my case, i have four blocks based on a single table. Based on one column in Block1, one of BLOCKS (BLOCK2, BLOCK3, BLOCK4) will get enabled. So should i go like how LittleFoot explained or any other way? Please help me in this regard.

As it takes MINUTES to create a sample form based on Scott's tables, I hope you took that effort and checked whether it works or not. Because, it's been 6 hours between you posted a question & me seeing it.